UFC 3-430-07
24 July 2003
including Change 1, Jan 2004 and Change 2, March 2005
operation of the valve or by observing any excessive vibration of the valve as it operates
under pressure.
7-6.3
Pressure Reducing Valves. While there is pressure on the system, open
and then close the by-pass valve, as safety and operating conditions permit, and
observe the fluctuation of the pressure gage pointer as an aid in determining possible
defects in the operation of the pressure reducing valve or the pressure gage. Look for
evidence that may indicate improper condition of the relief or safety valves provided for
pressure reducing valves.
7-6.4
Safety and Safety Relief Valves. Inspect the valves for evidence of
leaks and proper operation. Check the popping pressure and blow-down of safety
valves by allowing the pressure of the boiler to rise so that the valves lift. Inspect the
valve drains and discharge to ensure that they are free from obstructions and installed
according to the ASME Code. For multiple valve operations, where an accumulation
test cannot be accomplished, check the freedom of the valve to lift using the lifting lever
provided the pressure is within 10 percent of the valve set pressure. Similarly, check
safety relief valves by using the lifting lever. Proper installation and operation is
necessary prior to issuing an inspection certificate.
7-7
BOILER AUXILIARIES. While the boiler is operating under normal
conditions, observe the operation of all boiler auxiliaries for any defects that may
prevent the proper functioning of the boiler or which may indicate a lack of proper
maintenance. Discourage the unnecessary use of multiple auxiliaries or the use of a
large auxiliary during a light load period (when a smaller auxiliary could be substituted.)
Steam leaks, wastage to atmosphere, and so forth, should be called to the attention of
the operating personnel. Particular attention should be given to deaerator venting
practice. Venting should be held to the minimum required to preclude oxygen
entrainment in the feedwater. When intermittently operating condensate pumps are
used, look for any tendency toward the creation of a vacuum when a pump starts. If this
happens, the installation of a small continuously operating, float throttled, condensate
pump (in parallel with intermittently operating pumps) will ensure a condensate flow at
all times. If there are a number of intermittently operating condensate pumps, it may be
possible to convert one of them (if of small enough capacity) to continuous throttled
operation.
7-8
BOILER AND FEEDWATER TREATMENT. Observe the operation of
equipment provided for boiler and feedwater treatment, and check the materials and
procedures used for boiler and feedwater treatment to ensure adequate protection
against scale and corrosion in the boiler, plant, equipment, and distribution system. The
internal condition of the boilers, as evidenced from inspections required under Chapter
4, "Internal Inspection," is the determining factor regarding the adequacy of materials,
and procedures used in boiler and feedwater treatment. Withhold the certificate if an
effective boiler water treatment program is not being implemented.
7-9
FUEL HANDLING PRACTICES. Check the fuel handling practices and
make recommendations toward the elimination of multiple handling, heating of tanks not
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